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CONICAL CATENARY


Curve studied by Bobillier in 1829.

The conical catenary is the equilibrium line of an inelastic flexible homogeneous infinitely thin massive wire included in a cone of revolution, placed in a uniform gravitational field.
 
Differential equation:  (see at general catenary), where  is the normal vector of the cone.

Case of the vertical cone with vertex O and half-angle a, parametrization based on the polar coordinates of the development plane: .
Differential equation (the derivatives are taken with respect to q) (with ). Notice that it does not depend on a.


 
Conical catenary with hyperbolic development
(but that is not a hyperbola!)
Differential equation in the case where :
Parametrization:  (rectangular hyperbola in the development plane).

 
 
 
Here are 3 catenaries based on a vertical cone with identical development (on the left), with different opening angles

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© Robert FERRÉOL, Alain ESCULIER 2018